Millet was a self‑pollinating crop with many small flowers, which made it difficult to emasculate millet. For this purpose, a self‑made temperature control device for millet emasculation was made, which consisted of a heating barrel, a power supply and a bracket. The heating barrel was composed of a control circuit and a temperature control part. The heating barrel was the main body of the device, and emasculation took place in this space. The control circuit included temperature setting and time setting circuit, and the circuit had setting, display, timing, countdown alarm and other functions. The temperature control part of the heating barrel was composed of four materials such as thin steel wire mesh, electric heating sheet, insulation layer and metal shell. The temperature in the barrel could reach the set temperature and maintain a stable state to meet the requirements of emasculation. In order to verify the emasculation effect of the device, Jingu 21 and Qinhuang 2 millet varieties were selected, and the pollen viability, emasculation rate and undamaged pistillate rate were measured. The results showed that the longer the treatment time at the same temperature, the lower the pollen viability was. After treatment at 48 ℃ for 10-15 min or 52 ℃ for 10 min for Jingu 21 and at 48 ℃ for 10-15 min for Qinhuang 2, both the undamaged pistillate rate and emasculation rate were significantly improved, and the effect of emasculation was the best, which proved that the device could be effectively emasculated.